Toilet ventilation device

ABSTRACT

The toilet ventilation device is used for drawing air from inside a toilet bowl of a toilet having a toilet tank and having an overflow pipe located inside the toilet tank. The device includes an adaptor fitting over an opened top end of the over-flow pipe. The adaptor forms a first bottom- opened chamber and a second bottom-opened chamber that are in fluid communication with one another through a restricted flow passage. At least one among the first and the second chamber is configured and disposed to surround the top end of the overflow pipe and creates an oversized hood extending substantially parallel to an outer wall surface of the overflow pipe. The open bottom of the first and of the second chamber is located below a filled water level. The device also includes an air conduit network extending between the outlet of the adaptor to outside the toilet.

CROSS-REFERENCE TO RELATED APPLICATION

The present case claims the benefit of U.S. patent application No. 61/344,211 filed 11 Jun. 2010, which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The technical field relates generally to toilet ventilation devices.

BACKGROUND

Many different toilet ventilation devices have been suggested over the year. These devices are often operated after or during use of a toilet to extract odoriferous air, having unwanted odor resulting from use of the toilet and generally coming from the toilet bowl. The devices are often connected to a ventilation conduit or pipe leading outside to expel the odoriferous air.

Some toilet ventilation devices extract odoriferous air through the top end of the overflow pipe provided in toilet tanks. The overflow pipe is already in fluid communication with the interior of the toilet bowl. Creating a vacuum pressure inside the overflow pipe can thus draw air from inside the toilet bowl. Examples of devices using this approach are disclosed for instance in U.S. Pat. No. 1,342,716 (Johnston) issued 8 Jun. 1920, in U.S. Pat. No. 3,626,554 (Martz) issued 14 Dec. 1971 and in U.S. Pat. No. 4,583,250 (Valarao) issued 22 Apr. 1986.

The filled water level in a toilet tank is normally relatively close to the top end of the overflow pipe. Additionally, the available space between the top end of the overflow pipe and the tank lid is often very limited. One of the challenges in designing a toilet ventilation device operating under a vacuum pressure in this context is preventing water from possibly leaking out of the toilet through the toilet ventilation device. A toilet ventilation device generally operates before the toilet is flushed and continues to operate while it is flushed. When the toilet is flushed, internal splashes due to the sudden variations of the pressure at the inlet of the toilet ventilation device may happen. These splashes generate airborne water drops that can potentially be carried out with the extracted air. In some cases, several successive internal splashes created while the toilet ventilation device operates can ultimately result in a leak. This made the prior toilet ventilation devices considerably less attractive for their widespread use.

Accordingly, there is still room for many improvements in this area of technology.

SUMMARY

In one aspect, there is provided a toilet ventilation device for drawing air from inside a toilet bowl of a toilet having a toilet tank and having an overflow pipe located inside the toilet tank, the device including: an adaptor fitting over an opened top end of the overflow pipe, the adaptor forming a first bottom-opened chamber and a second bottom-opened chamber that are in fluid communication with one another through a restricted flow passage, at least one among the first and the second chamber being configured and disposed to surround the top end of the overflow pipe and create an oversized hood extending substantially parallel to an outer wall surface of the overflow pipe, the open bottom of the first and of the second chamber being located below a filled water level, the adaptor defining an internal air path extending from the first chamber to an outlet of the adaptor positioned downstream of the second chamber; and an air conduit network extending between the outlet of the adaptor and outside the toilet tank.

In another aspect, there is provided an adaptor of a ventilation device for a toilet, the adaptor being insertable over an overflow pipe located inside a toilet tank of the toilet, the adaptor having an internal air path extending from inside the overflow pipe and an outlet of the adaptor, the adaptor including: a first vertically-extending tube fitting over an opened top end of the overflow pipe, the first vertically-disposed tube having a bottom opened end; a second vertically-extending tube that is juxtaposed to the first vertically-extending tube and having a bottom opened end, the first and the second vertically-extending tube being in fluid communication through a restricted flow passage; and an outlet tube having a first end connected to the second vertically-extending tube, and a second end, opposite the first end, defining the outlet of the adaptor, the internal air path passing through the first vertically-extending tube, the restricted flow passage, the second vertically-extending tube and then the outlet tube.

In another aspect, there is provided a method of mitigating water ingestion in a toilet ventilation device for a toilet having a toilet tank, the method including: mounting an adaptor over an overflow pipe extending vertically inside the toilet tank of the toilet, the adaptor forming an oversized hood surrounding a top end and an outer wall surface of the overflow pipe; filing the toilet tank up to a filled water level; applying a vacuum pressure at an outlet of the adaptor to draw air coming from inside a toilet bowl of the toilet through the overflow pipe; upon flushing the toilet, preventing airborne water drops, caused by at least one splash occurring inside the adaptor as the water level goes down in the toilet tank, from coming out of the adaptor through the outlet.

In another aspect, there is provided a manufacturing process for making an adaptor for a toilet ventilation device as defined herein.

Further details on these aspects as well as other aspects of the proposed concept will be apparent from the following detailed description and the appended figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a front and partially-cutaway isometric view illustrating an example of a toilet ventilation device installed on a generic toilet;

FIG. 2 is a view similar to FIG. 1 but taken from another angle and partially showing the interior of the toilet bowl;

FIG. 3 is an isometric view illustrating only the toilet ventilation device of FIG. 1;

FIG. 4 is an enlarged cross sectional view illustrating the adaptor of the toilet ventilation device of FIG. 1 mounted on the overflow pipe of the toilet; and

FIGS. 5 to 9 are views illustrating other examples of adaptors for the toilet ventilation device.

DETAILED DESCRIPTION

FIG. 1 is a front and partially-cutaway isometric view illustrating an example of a toilet ventilation device 10 installed on a generic toilet 12 located inside a room, for instance a bathroom. The room can be located inside a larger construction, for instance a building or a construction that is not a building, such as a boat or a recreational vehicle, to name just a few.

The following description will refer to a building for the sake of simplicity but this is not limitative.

The toilet 12 has a toilet tank 14 and the toilet bowl 16. The interior of the toilet bowl 16 is shown in FIG. 2, which is a view similar to FIG. 1 but taken from another angle. The toilet bowl 16 receives a toilet seat 18 that is pivotally connected to the upper rim of the toilet bowl 16. The illustrated toilet 12 also has a seat cover 20 pivotally connected to the rear of the upper rim of the toilet bowl 16. The toilet tank 14 is connected over the rear end of the toilet bowl 16. Variants are also possible. The toilet tank 14 stores the water required to flush the toilet 12 so as to force the liquid and solid contents inside the toilet bowl 16 through a bottom outlet and then into a sewer discharge pipe 22 (FIG. 2). FIG. 1 shows the toilet tank 14 empty for the sake of clarity.

The toilet tank 14 is opened at the top. This opening is generally closed by a tank lid 24 having a shape complementary to that of a rim 26 (FIG. 1) surrounding the opening of the toilet tank 14. The tank lid 24 is slightly larger than the opening.

The toilet 12 is connected to a pressurized water supply line that sends water to a valve unit 30 (FIG. 1) located inside the toilet tank 14. The valve unit 30 is provided to control the filling of the toilet tank 14 up to a filled water level L (FIG. 2). The valve unit 30 often includes an actuation mechanism using a float or the like (not shown). Many different arrangements can be used to control the water level, as is well known in the related art. Water fills the toilet tank 14 immediately after a flush if the water supply line is pressurized.

The toilet 12 includes an overflow pipe 40 extending vertically inside the toilet tank 14. The overflow pipe 40 has an opened top end that is configured and disposed to prevent the water level from rising above a certain limit in case of a failure or an error in setting the valve unit 30. The overflow pipe 40 has an opened bottom end that is in fluid communication with the toilet bowl 16. This way, if the water level goes above the filled water level L and continues to rise for some reason, the excess water can leave the toilet tank 14 through the top end of the overflow pipe 40 so as to prevent water level from reaching the rim 26 of the toilet tank 14 and causing a major water leak into the room.

As shown in FIG. 1, the valve unit 30 includes a bowl refill tube 32 that is inserted through the top end of the overflow pipe 40. The bowl refill tube 32 ensures that the bottom of the toilet bowl 16 is filled up to an appropriate water level. This way, should the water level inside the toilet bowl 16 be too low after a flush, the added water will bring the water level up. Water flows in the bowl refill tube 32 when the toilet tank 14 is being filled. Thus, as soon as the water reaches the filled water level L and the valve unit 30 stops the water supply inside the toilet tank 14, the water flow through the bowl refill tube 32 will be stopped as well.

Flushing the toilet 12 involves quickly sending most of the water from the toilet tank 14 through a flush conduit 50 that is in fluid communication with the toilet bowl 16. The flush conduit 50 is normally closed by a pivotable rubber flapper 52 that is configured and disposed to open when someone flushes the toilet 12. As is well known, activating the flush handle 54 (FIG. 1) of the toilet 12 will lift the flapper 52 and force it to detach from its bottom closed position. This begins a flush cycle. The flapper 52 will then partially float while the water rushes out of the toilet tank 14 through the flush conduit 50. The sudden rush of water in the toilet bowl 16 washes the toilet bowl content. The flapper 52 normally closes by itself by gravity when the water level in the toilet tank 14 is relatively low. The supply of water inside the toilet tank 14 continues until the water level reaches the filled water level L once again. This ends the flush cycle.

In FIG. 1, the flapper 52 is shown in an opened position. The flapper 52 is shown in a closed position in FIG. 2.

At the beginning of the flush cycle, water will be directed to a space 56 (FIG. 2) below the flush conduit 50 before it goes inside the toilet bowl 16. Since the space 56 is in direct fluid communication with the opened bottom end of the overflow pipe 40, some water will go inside the overflow pipe 40 at the beginning of the flush cycle. For a brief moment, the water level inside the overflow pipe 40 will be substantially the same as the lowering water level inside the toilet tank 14. When the flapper 52 closes, the remaining water inside the overflow pipe 40 drains into the space 56.

In the illustrated example, the vacuum source required to operate the toilet ventilation device 10 includes a fan unit 60 connected to a nearby wall section located behind the toilet 12. It is also possible to locate the fan unit 60 a few meters away or even elsewhere, for instance on the floor. Still, one can also use a remote vacuum source located outside the room and not use the fan unit 60 near the toilet 12 to draw air therefrom.

The fan unit 60 includes a fan having a plurality of blades driven into rotation by an electric motor, for instance a 12-volt DC motor or the like. The rotation of the blades will create a vacuum pressure at an inlet 60 a of the fan unit 60. A skilled reader will understand that the vacuum pressure is selected so as to draw enough air from the device 10 to be efficient in removing odoriferous air but the vacuum pressure should not be high enough to syphon the water. Given the relative low clearance between the filled water level and the air inlet of the device 10, applying a high vacuum pressure, for instance the vacuum pressure of a domestic vacuum cleaner, is likely to syphon the water. The device 10 will require a moderated vacuum pressure. A sufficient minimum height is also maintained between the water level and the outlet of each bottom-opened part of the device 10.

The electric motor of the fan unit 60 can be switched on and off by the user through a corresponding switch or the like. In other implementations, the switch can be made automatic and/or can be linked to another device, for instance the lighting system of the room where the toilet 12 is located. Other variants include an automatic switch within the toilet seat 18 or a proximity sensor, to name just a few. The switch can also be coupled to a timer for interrupting the operation of the electric motor after a given running time, for instance from 1 to 4 minutes. Many other variants are possible as well.

If desired, the same fan unit 60 can be connected to a plurality of devices 10, each being mounted on a corresponding toilet, and be made powerful enough to draw air from all the toilet bowls simultaneously.

The fan unit 60 has an outlet 60 b that is connected to an exhaust conduit 62 (FIG. 2) to expel the odoriferous air outside the room, for instance outside the building. In other implementations, the odoriferous air can be treated or partially treated before being returned inside the room or somewhere else in the building.

FIG. 3 is an isometric view illustrating only the toilet ventilation device 10 of FIG. 1.

In the present concept, air enters the toilet ventilation device 10 through a component called an “adaptor” 70 that is mounted over the top end of the overflow pipe 40. This adaptor 70 is designed to prevent the ingestion of water by the toilet ventilation device 10 while still not preventing the overflow pipe 40 from functioning in case of an overflow. It does not have any moving parts.

FIG. 4 is an enlarged cross sectional view illustrating the adaptor 70 of the device 10 of FIG. 1 when mounted on the overflow pipe 40 of the toilet 12. As best shown in FIG. 4, the adaptor 70 includes a first vertically-extending tube 72 opened at the bottom and mounted over the top end of the overflow pipe 40. The first vertically-extending tube 72 defines a first chamber 74 that creates an oversized hood. The first vertically-extending tube 72 has an inner diameter larger than the outer diameter of the overflow pipe 40. The first chamber 74 includes a first and a second portion, the first portion being generally located above the top end of the overflow pipe 40, and a second portion extending downwards along the outer wall surface of the overflow pipe 40.

The first vertically-extending tube 72 has a closed top end. The first vertically-extending tube 72 can be connected to the overflow pipe 40 using different arrangements, such as an arrangement including side screws engaging the outer wall surface of the overflow pipe 40 or an arrangement including an element resting over the edge of the top end of the overflow pipe 40, to name just a few.

FIGS. 1 to 3 show that the bowl filling tube 32 can be inserted through corresponding holes made in the adaptor 70. The bowl refill tube 32 is inserted deep inside the overflow pipe 40. The holes through the adaptor 70 can be made small enough so as to create a tight fit with the outer surface of the bowl filling tube 32. If desired, the distal end of the bowl filling tube 32 can be blocked using a plug 76 (FIG. 4) or the like. A slit 78 can be made through its wall near the plug 76 for allowing the pressurized water to exit the bowl refill tube 32 during a flush cycle. The slit 78 however closes by itself when the interior pressure is gone. This prevents air coming from above the filled water level through the valve unit 30 and then through the bowl refill tube 32 from being aspirated into the toilet ventilation device 10. This may happen with some models of valve units 30.

The first vertically-extending tube 72 is in fluid communication with a second vertically-extending tube 80, juxtaposed to the first vertically-extending tube 72, and that also has an opened bottom end. The first and the second vertically-extending tube 72, 80 communicate through a side port 82 made through their respective side wall. The side port 82 creates a lateral restricted flow passage. In the illustrated example, the restricted flow passage is formed by a short horizontal tube extending inside the first chamber 74 and having a beveled end engaging the edge of the top end of the overflow pipe 40. The beveled section is located on the top side. This mitigates water ingestion in case of a splash occurring inside the first chamber 74.

Air leaves the adaptor 70 through an outlet tube 84 located on the side wall of the second vertically-extending tube 80. The outlet tube 84 is located vertically higher than the side port 82 between the two tubes 72, 80. This way, any water drops carried with the air have an additional opportunity of falling by gravity when they are within the second vertically-extending tube 80. They can thus go back inside the toilet tank 14 through the opened bottom end of the second vertically-extending tube 80. The interior of the second vertically-extending tube 80 defines a second chamber 86.

Between the adaptor 70 and outside the toilet tank 14 is provided a network of air conduits. The exact configuration and arrangement may vary from one implementation to another. As shown in FIGS. 1 to 3, the outlet of the adaptor 70 is connected to the inlet 90 of a J-shaped (“hook” shaped) air conduit 92 using an intermediary air conduit 94, for instance a flexible air conduit located above the filled water level.

In the illustrated example, and as best shown in FIG. 3, the inlet 90 of the J-shaped air conduit 92 includes an L-shaped inlet portion 96 whose opposite end 98 is opened and located below the filed water level when installed in the toilet tank 14. This way, if some airborne water drops manage to reach the inlet 90 after passing through the intermediary air conduit 94, they can return inside the toilet tank 14 through the end 98.

The inlet portion 96 has an upper longitudinal slot 100 to which is connected to the inlet of a flat portion 104 of the air conduit 92. The flat portion 104 has a curved upper end 106. The flat portion 104 is made relatively thin so as to fit easily between the rim 26 of the opening of the toilet tank 14 and the tank lid 24. It is made relatively large in width so as to increase the cross section area and compensate for the reduced thickness. The curved upper end 106 allows the weight of the air conduit 92 to be supported by the toilet tank 14. Most of the air conduit 92 is located outside the back wall of the toilet tank 14. The outlet of the air conduit 92 includes a horizontally-extending outlet portion 108. One of the ends of the outlet portion 108 is closed and the other is opened. This opened end 110 is connected to another intermediary air conduit 112, for instance a flexible air conduit, whose opposite end is connected to the inlet 60 a of the fan unit 60 in the illustrated example.

Also in the illustrated example, the various air conduits of the device 10, with the exception of the flat portion 104 of the air conduit 92, have a circular cross section. The diameter of the air conduits can be for instance between 1.25 cm (0.5 inch) and 2.5 cm (1.0 inch). Variants are also possible. Still, the air conduits can have other shapes and/or diameters.

When the air conduit 92 is hooked to the toilet tank 14, it may create a small inclination of the tank lid 24. To ensure a more uniform fit, the rim and/or the bottom of the tank lid 24 can include pads and/or strips of a foam-like material to slightly raise the height of the tank lid 24 and level it. The foam-like material can also be used to reduce the air leaks between the rim 26 of the toilet tank 14 and the tank lid 24. However, some air should still be allowed to flow inside the toilet tank 14 to compensate for the water level drop during a flush. Sealing the interior of the toilet tank 14 may otherwise prevent water from flushing properly.

It should be noted that network of air conduits can be designed differently than what is shown and described herein. For instance, one can provide a hole through the upper top portion of one of the walls of the toilet tank 14 for allowing air to exit the toilet tank 14.

FIG. 2 shows the spaced-apart holes 120 that are generally provided through the walls of the toilet bowl 16 and through which some of the water flows during a flush. These holes 120 are in fluid communication with a peripheral chamber 122 inside the rim of the toilet bowl 16. The peripheral chamber 122 has a rear section that is in fluid communication with the overflow pipe 40 through the space 56. Thus, applying a vacuum pressure at the top end of the overflow pipe 40 can draw air from inside the toilet bowl 16 through the holes 120.

In the example illustrated in FIGS. 1 to 4, the edge of the bottom end of the first vertically-extending tube 72 is vertically higher than the edge of the bottom end of the second vertically-extending tube 80. When the toilet tank 14 is filled up to the filled water level L, the edges will be immerged and this seals the bottom of the first chamber 74 inside the first vertically-extending tube 72 from the air above the water. During a flush, the water level goes down inside the toilet tank 14 and the bottom of the adaptor 70 will be out of the water at some point. When this happens while a vacuum pressure is applied, the first chamber 74 inside the first vertically-extending tube 72 will be the first to go from a vacuum pressure to a pressure closer to the atmospheric pressure. This transition will cause an internal splash of water and may create airborne water drops. This phenomenon is often amplified by the fact that the overflow pipe 40 will be filled with water at the beginning of the flush cycle. No air will flow through the network of conduits until the water level drops and the bottom of the first vertically-extending tube 72 is out of the water. When the splash occurs, airborne water drops can fall down by gravity within the first vertically-extending tube 72 itself but some may be carried towards the second vertically-extending tube 80 where they can fall by gravity. When the falling water level inside the toilet tank 14 reaches the bottom edge of the second vertically-extending tube 80, the pressure inside the second chamber 86 will be at a smaller vacuum pressure compared to the vacuum pressure at the beginning of the flush cycle because the first chamber 74 will be opened at the bottom. The internal splash inside the second camber 86 will be smaller and less likely to generate airborne water drops that can reach the outlet 84 of the adaptor 70.

FIGS. 5 to 9 are isometric views illustrating other examples of adaptors for the toilet ventilation device 10.

In FIG. 5, the adaptor 200 includes a first vertically-extending tube 202 having an opened bottom end and a closed top end. It also includes a second vertically-extending tube 204 also having an opened bottom end and a closed top end. The second vertically-extending tube 204 is juxtaposed to the first vertically-extending tube 202. The fluid communication between the tubes 202, 204 is provided by a first horizontal tube 206 extending through their walls. Both ends of the horizontal tube 206 are beveled and its bottom outer surface rests on the top end edge to support the weight of the adaptor 200. Inside the first vertically-extending tube 202, the longer side of the horizontal tube 206 is provided at the bottom to mitigate water ingestion in case of an internal splash. However, the opposite end is beveled on the reverse side and this acts as a guard to stop airborne water drops, if any. A second horizontal tube 210 is provided vertically above the first horizontal tube 206 through the side wall of the second vertically-extending tube 204. This second horizontal tube 210 has a beveled inlet end 212, also to mitigate water ingestion. The opposite end 214 of the second horizontal tube 210 constitutes the air outlet of this adaptor 200. Optionally, the second horizontal tube 210 includes one or more spaced-apart annular baffles 220 coaxially disposed therein. Each baffle 220 can stop water drops adhering on the inner wall of the second horizontal tube 210. Water upstream the first baffle 220 can then go back into the second vertically-extending tube 210 once the vacuum pressure is interrupted and/or the water can evaporate. Water between the two spaced-apart baffles 220 can evaporate over time.

In FIG. 6, the adaptor 300 includes a first vertically-extending tube 302 mounted over the top end of the overflow pipe 40. The adaptor 300 also includes two opposite second vertically-extending tubes 304, 306 that are juxtaposed to the first vertically-extending tube 304. The two second vertically-extending tubes 304, 306 are opened at the top and at the bottom. They are each in fluid communication with the first vertically-extending tube 302 through respective side tubes 310, 312. The inner end of each side tube 310, 312 is beveled and their bottom outer surface rests on the top end edge of the overflow pipe 40 to support the weight of the adaptor 300. The longer side of the tubes 310, 312 is disposed at the bottom to mitigate water ingestion in case of an internal splash inside the first vertically-extending tube 302. The top ends of the second vertically-extending tubes 310, 312 are in fluid communication with one another through a common top horizontal tube 308. The outlet 314 of the horizontal tube 308 is the outlet of the adaptor 300.

In FIG. 7, the adaptor 400 includes a first vertically-extending tube 402 set over the top end of the overflow pipe 40. The first vertically-extending tube 402 rests on the edge of the top end using a rod-like element 404 axially extending inside the first vertically-extending tube 402. The first vertically-extending tube 402 defines a first chamber 406. Air inside the first chamber 406 inside the first vertically-extending tube 402 goes through a first elbow conduit 408 located above the first vertically-extending tube 402. The first elbow conduit 408 is connected to a second elbow conduit 410 having a bottom opened end in fluid communication with a second vertically-extending tube 412, also having an opened bottom end.

In FIG. 8, the adaptor 500 includes a first vertically-extending tube 502 mounted over the top end of the overflow pipe 40. It also includes a second vertically-extending tube 504 coaxially disposed over the first vertically-extending tube 502. The weight of the adaptor 500 rests on the top end edge of the overflow pipe 40 using rod-like elements 508. Spacers 510 are provided near the bottom end of the two vertical tubes 502, 504 to maintain them centered. The first vertically-extending tube 502 includes side openings 520 near the top end thereof. Air from inside the first vertically-extending tube 502 can then pass directly inside the second vertically-extending tube 504. Air exits the second vertically-extending tube 504 through a port 522 made in its top wall. Air then enters a top horizontal tube 524, from which the air exits the adaptor 500.

In FIG. 9, the adaptor 600 includes a first vertically-extending tube 602 set over the top end of the overflow pipe 40. The first vertically-extending tube 602 rests on the edge of the top end using a rod-like element 604 axially extending inside the first vertically-extending tube 602. The rod-like element 604 supports a conical member 606 that is coaxially disposed above the overflow pipe 40. An annular space 610 is formed between the periphery of the bottom edge of the conical member 606 and the top end edge of the overflow pipe 40. In this adaptor 600, the first chamber is formed under the conical member 606 and the second chamber is defined inside the first vertically-extending tube 602, outside the overflow pipe 40 and the conical member 606. Air can flow from the overflow pipe 40 to inside the first vertically-extending tube 602 by passing through the annular space 610. Air rushing out through the annular space 610 creates an air curtain that can mitigate the water drops. Air can exit the adaptor 600 through a top L-shaped tube 612 whose inlet end 614 extends through the first vertically-extending tube 602 right above the top surface of the conical member 606.

The device 10 can be made using a manufacturing process that includes any one of the following acts or combinations thereof: cutting, bending, punching, molding, gluing, painting.

Overall, the proposed concept provides a way to ensure a good interface between the top end of the overflow pipe 40 and the toilet ventilation device 10 while minimizing the risks of causing a water leak through the toilet ventilation device 10. It also provided a method of mitigating the risks of water ingestion in a toilet ventilation device 10.

The present detailed description and the appended figures are meant to be exemplary only. A skilled person will recognize that variants can be made in light of a review of the present disclosure without departing from the proposed concept. 

1. A toilet ventilation device for drawing air from inside a toilet bowl of a toilet having a toilet tank and having an overflow pipe located inside the toilet tank, the device including: an adaptor fitting over an opened top end of the overflow pipe, the adaptor forming a first bottom-opened chamber and a second bottom-opened chamber that are in fluid communication with one another through a restricted flow passage, at least one among the first and the second chamber being configured and disposed to surround the top end of the overflow pipe and create an oversized hood extending substantially parallel to an outer wall surface of the overflow pipe, the open bottom of the first and of the second chamber being located below a filled water level, the adaptor defining an internal air path extending from the first chamber to an outlet of the adaptor positioned downstream of the second chamber; and an air conduit network extending between the outlet of the adaptor and outside the toilet tank.
 2. The toilet ventilation device as defined in claim 1, wherein the hood is created by the first chamber, the first chamber including a first and a second portion, the first portion being generally located vertically above the top end of the overflow pipe, and a second portion generally surrounding the overflow pipe below an edge of the top end of the overflow pipe.
 3. The toilet ventilation device as defined in claim 2, wherein the first chamber is defined inside a first vertically-extending tube and the second chamber is defined inside a second vertically-extending tube.
 4. The toilet ventilation device as defined in claim 3, wherein the first vertically-extending tube is coaxially-disposed with reference to the overflow pipe when the adaptor is mounted thereon. 5-6. (canceled)
 7. The toilet ventilation device as defined in claim 4, wherein the first and the second vertically-extending tube are juxtaposed to one another, the restricted flow passage being provided through corresponding side walls of the first and the second vertically-extending tube.
 8. The toilet ventilation device as defined in claim 7, wherein the restricted flow passage is vertically higher than the edge of the top end of the overflow pipe.
 9. The toilet ventilation device as defined in claim 8, wherein the first and the second vertically-extending tube each have a bottom opened end that correspond to the bottom end of the first and the second chamber, respectively, the bottom ends of the first and the second vertically-extending tube extending below the filled water level of the toilet tank, the bottom end of the second vertically-extending tube being vertically below the bottom end of the first vertically-extending tube.
 10. (canceled)
 11. The toilet ventilation device as defined in claim 1, wherein the restricted flow passage includes a horizontally-extending tube, the horizontally-extending tube having at least one beveled end.
 12. The toilet ventilation device as defined in claim 10, wherein the horizontally-extending tube engages the edge of the top end of the overflow pipe when the adaptor is mounted thereon, at least a part of the weight of the adaptor being supported by the horizontally-extending tube.
 13. The toilet ventilation device as defined claim 1, wherein the air conduit network includes a substantially J-shaped air conduit having a curved top end, the curved top end being configured and disposed to fit between a top edge of a toilet tank wall and a bottom surface of a tank lid of the toilet.
 14. The toilet ventilation device as defined in claim 13, wherein the J-shaped air conduit includes an inlet portion having a first end located above the filled water level and a second end located below the filled water level, the first end of the inlet portion being connected to the outlet of the adaptor through an intermediary air conduit.
 15. The toilet ventilation device as defined in claim 14, wherein the intermediary air conduit is made of a flexible material and is positioned above the filled water level, the device further including a fan unit to create a vacuum pressure inside the adaptor, the fan unit is located outside the toilet tank. 16-17. (canceled)
 18. An adaptor of a ventilation device for a toilet, the adaptor being insertable over an overflow pipe located inside a toilet tank of the toilet, the adaptor having an internal air path extending from inside the overflow pipe and an outlet of the adaptor, the adaptor including: a first vertically-extending tube fitting over an opened top end of the overflow pipe, the first vertically-disposed tube having a bottom opened end; a second vertically-extending tube that is juxtaposed to the first vertically-extending tube and having a bottom opened end, the first and the second vertically-extending tube being in fluid communication through a restricted flow passage; and an outlet tube having a first end connected to the second vertically-extending tube, and a second end, opposite the first end, defining the outlet of the adaptor, the internal air path passing through the first vertically-extending tube, the restricted flow passage, the second vertically-extending tube and then the outlet tube.
 19. The adaptor as defined in claim 18, wherein the first vertically-extending tube includes a first and a second portion, the first portion being generally located vertically above the top end of the overflow pipe, and a second portion generally surrounding an outer wall surface of the overflow pipe.
 20. The adaptor as defined in claim 19, wherein the first vertically-extending tube is coaxially-disposed with reference to the overflow pipe when the adaptor is mounted thereon. 21-22. (canceled)
 23. The adaptor as defined in claim 18, wherein the restricted flow passage is provided through corresponding side walls of the first and the second vertically-extending tube, the restricted flow passage being vertically higher than an edge of the top end of the overflow pipe.
 24. The adaptor as defined in claim 18 wherein the bottom end of the second vertically-extending tube is vertically below the bottom end of the first vertically-extending tube. 25-27. (canceled)
 28. A method of mitigating water ingestion in a toilet ventilation device for a toilet having a toilet tank, the method including: mounting an adaptor over an overflow pipe extending vertically inside the toilet tank of the toilet, the adaptor forming an oversized hood surrounding a top end and an outer wall surface of the overflow pipe; filing the toilet tank up to a filled water level; applying a vacuum pressure at an outlet of the adaptor to draw air coming from inside a toilet bowl of the toilet through the overflow pipe; upon flushing the toilet, preventing airborne water drops, caused by at least one splash occurring inside the adaptor as the water level goes down in the toilet tank, from coming out of the adaptor through the outlet.
 29. The method as defined in claim 28, wherein preventing airborne water drops from coming out of the adaptor through the outlet includes passing air between two juxtaposed bottom-opened chambers through a lateral restricted air passage, the chambers and the restricted air passage being located inside the adaptor, one of the chambers surrounding the top end of the overflow pipe.
 30. The method as defined in claim 29, wherein preventing airborne water drops from coming out of the adaptor through the outlet includes having the bottom of the chamber surrounding the top end of the overflow pipe being out the water, when the water level goes down, before the bottom of the other chamber. 31-32. (canceled) 